Internal-combustion engine



P. HENTSCHKE.

INTERNAL comsusnom ENGINE.

APPLICATION FILED JAN. 23. I920.

' PatentedNov. 29,1921.

Min 55: I MM PAUL HENTSCEKE, OF LOS ANGELEE,

1N TERM AL-COiVfBUSTZON EN GENE.

Specification of Letters Yatent.

Fatented Nov. 29,

Application filed January 23, 1920. Serialjtlo. 353,558.

specification.

The present invention relates to improve ments in internal combustion engines, in which liquid fuel is deposited intermittently in an auxiliary combustion chamber which is in communication with a working cylinder and by the temperature dueto the compres sion of the air. charge air explosion and injection of the chamber contents into the cylinder is effected. i

The passages through which the cylinder combustion space and said chamber communicr 'e are usually so much restricted that the co lpression and temperature rise in the chamber is so much delayed that the piston reaches approximately the inner dead center position. before the explosion and fuel injection takes place. With permanentpassages connecting the cylinder and the chamber it is however not possible to produce the explosion in the chamber at thesame desired time under all load conditions of the engine, because a variable amount of liquid fuel changes the temperature of the wall and of the explosive mixture within the-chamber to a considerable degree.

The consequence. of these. temperature variations are preignitions at light load with an unfavorable effect on the running parts of the engine or an unwelcome reduction in the loadcapacity of the engine, if the area of the passages from the cylinder to the chamber are reduced.

It is the'object of the present inventionto counteract the described influence of a variable fuel charge to the auxiliary combustion chamber on the, time of the explosion in said chamber of an'engine of the described order. This object, generally speaking, is accomplished by a mechanical control of part, or of all of the passages from the.

cylinder to the chamber, in such a manner that with a similar amount of liquid fuel intermittently deposited in the chamber a similar amount of compressed air is. ad mitted from the cylinder to the chamber.

The amount of fuel delivered by the fuel' pump of an engine depends primarily on the engine load, secondarily on the position of a hand control, or a device operative by speed changes of the engine; it is therefore possible to accomplish the object of my invention automatically by providing a connection between the above mentioned means for controlling of the air passages from the cylinder to the auxiliary combustion chamher with the means used for controlling of the amount of fuel delivered to the chamber, or as thecase may bev of the speed ofcthe engine. Said connection can either be made directly by common mechanical elements as levers, rods or eccentrics or in large engines by the applicatioaof a pump and a fluid as a power transmittlng medlum.

The accompanying drawings show some of several ways of accomplishing the object of the present invention, whichthough differing in the arrangements of the details are principally related to one another.

The figure represents a longitudinal section through the working cylinder and piston of an internal combustion engine of the described kind, and an arrangement of per- "charge of liquid fuel is delivered during the said compression stroke by apump 18 through pipe 4, check valve 5 and hollow stem of valve 6. The ressure rise within the chamber 3 is considgrably smaller than in the cylinder 1 due to sufficient restriction in the holes 2, fuel vapors with a certain amount of compressed air will, without" high enough to overcome the force of spring 7, which acts by means of collar 8on valve 6, then some compressed and, therefore heated air will pass through thelbpen valve 6, to the top portion of chamber 3 by way of the passage 9, ring grobve 10, and openings 11 in the plug v 12. This instantly" richest in fuel are violently expelled into.

the cylinder 1, where the fuel-mist is subjected to a high temperature and burns with v a receding piston, so that no considerable pressure-rise above compression-pressure is experienced.

It can be seen that by the adjustment of collar 8 and tension of spring 7, the time of the explosion in chamber-'3 and the in- 16 jection of the fuel-air mixture into the cylinder 1 can be so adjusted that the combustion in the cylinder 1 takes a desired course. However any change of lord in the engine, which necessitates a change of the amount 20 of fuel lelivered to the chamber 3, would also change the temperature of the inside Wall of the said chamber 3 ina direct relation to the: amount of fuel delivered; a larger amount of fuelwill lower the tem- 25. perature of the wall of chamber 3 and also of the fuel-air mixture to an even larger measure, so that the explosion in the-chamber 3 and the fuel injection into the, cylinder 1 is effected too-late for an efiicient combustion. A fresh adjustment of collar 8 and a suflicient release of the tension of spring 7 will allow more compressed and- I cooling effect of the larger amount of fuel.

p This readjustment of spring 7 is made in the arrangement showin in an automatic way by the movement of lever 13, Which serves as a. support for the lower end of spring 7 Lever 13 can be operated by the be cooled in the usual mannerby the introusual means for the control of the engine speed and also the control of the fuel pump 18. The said pump 18 is operated in the cycle of the engine by avariable stroke earn 16, to deliver an intermittent charge of liquid fuel to the chamber 3. The said fuel-charge is varied through the action of the governor 14, and it will be observed that the governor 14 by its action on ,sleeve15 and cam 16 alters the amount of fuel delivered by the pump 18, the said governor 14 alsoalters the position of lever 13 by means of lever 17 and therefore the tension of spring 7. i

pipe 4 to chamber 3 is accompanied by a release of the spring 7, a smaller amount of fuel is accompanied by a compression of the said spring 7, in other words by a corv respondingly larger or smaller air-charge through passage 9 to the chamber 3.".

It will be observed that the present invention also facilitates the starting voperation of the engine by supplying a surplus n5 ofcompressed air from the cylinder 1 to A larger amount of fuel delivered through the chamber 3, at a time when a low coinprcssion in the cylinder with the cold walls in the-chamber are opposed to the first heat producing explosion in the chamber 3. The operationof starting the cold engine can be facilitatedfto any desired de -ree by a further release of the said spring 7, till the cylinder 1 and chamber 3 have attained their normal operating temperature. 1

Chamber 3 is preferably Water cooled for the object of keeping the temperature in the heavy portion of same within an allowable limit, While the vital portions of the said chamber 3, near the seat of plug 12 and near the vpassages 2 are more effectively 8d cooled.

Fuel passing through the hollow stem of valve 6 is resorted to in order to keep said valve 6. at a lower temperature, while at the same time the advantage of preheat- .85 ing of the liquid fuel charge is gained.

A charge, of air, entering; the chamber through holes .2 during the compression stroke of the piston, creates a mixture of air, fuel vapors, and liquidfuel, while a second charge of compressed air from the cylinder is delivered back of the fuel-air mixturethrough passage 9 and valve 6. This latter. air charge still further compresses themixture and drives the larger portion of the said mixture to the lower half of the chamber 3, from whence it is expelled into the cylinder by the force of n the explosion created by the additional compression; the pure air remaining in the top portion of the chamber 3 during the latter part of the combustion and expansion period in the cylinder serves. as a scavenger in the chamber. j

It is understood that the" cylinder 1 may duction of aLcooling medium preferabl-ywater into the cooling jacket as indicated. It is further understood the chamber 3, the plug 12 and a topflange positioned on the said plug 12 are secured to the cylinder 1 by a suitable means. i

Variousmodifications may be made without departing from the spirit of my invention as claimed Iclaim: ..1 1; In an internal combustion engine of the class described, an expansion-cylinder in communication with an auxiliary combustion cylinder through a predetermined 120 number of restricted holes; a supply means adapted to charge the liquid fuel into the auxiliary combustion chamber in sequence with the cycle of the engine; a passage for of'compressed air from the expansion cylinder into the auxiliary combustion chamber in reversed order the amount of liquid fuel charged into the auxiliary combustion chamber for variable loads on the engine,

2. in a pneumatic fuel injection means in combination With an internal combustion engine and an auxiliary combustion chamher; a diametrically taperingspace integra with the said auxiliary combustion chamher; a predetermined area of holes, adapted to pass from the cylinder of the said engine into the diametrically tapering space, to maintain a flow of air into the said auxiliary combustion chamber during the compression stroke, and restricted to prevent preignition; a liquid fuel charging means, adapted to deliver fuel to the said diametrically tapering space, through the said auxiliary combustion chamber, against the restricted airflow from the said engine cylinderthrough the said predetermined area of holes, to create a preliminary fuel-air mixture; a secondary air delivery means, adapted to pass fronrthe engine cylinder into the said fuel injection means, to admit air under pressure and to expel by explosion, the fuel and air charge from the auxiliary combustion chamber, into the engine cylinder; a pure air retainer, adapted to scavenge the said auxiliary combustion chamber, for the following charge of liquid fuel; a Water jacket positioned around the diametrically tapering space, adapted to absorb the heat therefrom;

to admit a predetermined charge of air therethrough during the compression stroke of the said engine; a liquid-fuel charging means, adapted to deliver fuel into the said fuel-air atomizing and charging means, to I create a preliminary fuel-air mixture With the said charge of air; a compressed air delivery means leading from the engine cylinder into the said fuel-air atomizing and charging means, adapted to raise the pressure and temperature therein With. compressed air at a timedetermined in accordance to the fuel charge above the self i nition degree, to expel by explosion the contents thereof into the said cylinder; atom nerature controlling means integral with the said liquid-fuel charging means and. the compressed air delivery means, adapted to preheat the said fuel and tocool the said compressed air; a temperature controlling means integral with the body of the said auxiliary combustion chamber, adapted to hold a high temperature in the upper portionthereof and a low temperature in the lower portion thereof, as set forth. 1

PAUL HENTSCHKE. 

